This invention is concerned with improving the separation of finely divided fluidizable catalyst particles from gasiform reaction products. More particularly, the invention is concerned with the method and means for improving the separation of suspended catalyst particles from a gasiform stream in cyclonic separation equipment.
In the cyclone type of separator, a suspension comprising a gasiform material with entrained finely divided solid material is introduced into the separator in a tangential manner that imparts a spiral or centrifugal swirling motion or action to the suspension. The centrifugal action causes the solids to be thrown to the other wall of the cyclone separator and they then slide down the cyclone wall into a solids collecting hopper therebelow for withdrawal therefrom as by a standpipe or dipleg means. The gasiform material thus separated from the solids is removed as by a central open passageway extending from a plane beneath the suspension tangential inlet upwardly through the top of the cyclone separator. A particularly useful application of the device is in connection with organic reactions employing fluidizable catalyst particles such as the catalytic treatment of petroleum fractions by cracking, the synthesis of hydrocarbons from carbon monoxide and hydrogen, the conversion of methanol to liquid hydrocarbons or other fluid catalyst operation known in the art.
In modern day operations such as riser catalytic cracking operations, enormous amounts of catalyst suspended in gasiform materials are handled in riser catalytic cracking units and it is necessary to rapidly separate the suspensions into a catalyst phase and a gasiform phase after the suspension conversion operation has traversed the riser unit or conversion zone.